Because bone regeneration is generally required to obtain successful outcomes for many common orthopedic procedures, osteoregenerative products such as allograft, bone substitutes, morphogenic proteins and osteoregenerative mixes are widely used by clinicians. In these procedures, both compression-resistant and non-compression resistant bone substitutes are frequently mixed with allograft as well as autologous materials including marrow and bone.
Current procedures for harvesting autologous stem cells from bone marrow have incorporated methods to enhance stem cell filtering, mixing or seeding to improve viability of implant matrixes. For example, U.S. Pat. No. 5,824,084 (Muschler) discloses a method of preparing a composite bone graft. Unfortunately, some disadvantages are associated with these procedures. For example, the time and exposure required during the mixing of bone, bone substitutes matrix's with autologous bone or aspirate can significantly delay the surgical procedures, increasing the risk of infection and blood loss.
Also, the bone marrow aspiration procedure often requires an added surgery for harvesting of BMA or bone from adjacent vertebrae, processes, ribs or the iliac crest. Spinal surgical fusion procedures require the endplates to burred and roughened to allow marrow to bleed into the interbody graft. This added time and effort increases operating room demand, anesthesia requirements, infectious disease exposure, and blood loss, all of which impact patient outcomes as well as procedure cost. Lastly, conventional prefilled graft materials are not designed to maximize stem cell retention.
Thus, there is a need for a procedure and devices for harvesting stem cells that reduces collateral damage, infection risk, operating room time, operating room effort for graft mixing and packing, and provides a graft that enhances stem cell attachment.
US Published Patent Application No. 2008154377 (Voellmicke) discloses an intervertebral fusion cage that is adapted to contain an inserter within its inner volume during insertion of the cage.
Curylo, Spine, 24(5), 1 March 1999, pp 434-438 discloses augmentation of spinal arthrodesis with autologous bone marrow in a rabbit posterolateral spine fusion model.
Bo{hacek over (z)}idar {hacek over (S)}ebeèiæ, Croatian Medical Journal, March 1999 (Volume 40, Number 3) discloses percutaneous autologous bone marrow grafting on the site of tibial delayed union.
Becker, Spine, 31 (1), 2006, pp. 11-17, discloses osteopromotion by a β-tricalcium phosphate/bone marrow hybrid implant for use in spine surgery.